(Opto)electronic components such as semiconductors, transistors, integrated circuits (ICs), discrete devices, light emitting diodes (LEDs) and others known in the art are designed to operate at a normal operating temperature or within a normal operating temperature range. However, the operation of an (opto)electronic component generates heat. If sufficient heat is not removed, the (opto)electronic component will operate at a temperature significantly above its normal operating temperature. Excessive temperatures can adversely affect performance of the (opto)electronic component and operation of the device associated therewith and negatively impact mean time between failures.
To avoid these problems, heat can be removed by thermal conduction from the (opto)electronic component to a heat sink. The heat sink can then be cooled by any convenient means such as convection or radiation techniques. During thermal conduction, heat can be transferred from the (opto)electronic component to the heat sink by surface contact between the (opto)electronic component and the heat sink or by contact of the (opto)electronic component and heat sink with a TIM. The lower the thermal impedance of the medium, the greater the flow of heat from the (opto)electronic component to the heat sink.
Surfaces of the (opto)electronic component and the heat sink are typically not completely smooth, therefore, it is difficult to achieve full contact between the surfaces. Air spaces, which are poor thermal conductors, appear between the surfaces and increase impedance. These spaces can be filled by inserting a TIM between the surfaces. Therefore, there is a continuing need for TIMs with good thermal properties (high conductivity and low impedance) and heat stability (the grease resists viscosity increase with time) as devices become smaller and generate more heat.